Calcium-dependent regulation of membrane ion permeability in a cell line derived from the equine sweat gland epithelium. Academic Article uri icon

Overview

abstract

  • We measured the rates of 125I- and 86Rb+ efflux from preloaded, cultured equine sweat gland cells. The calcium ionophore ionomycin increased the efflux of both isotopes. Anion efflux was unaffected by Ba2+, but this cation inhibited 86Rb(+)-efflux, suggesting that [Ca2+]i-activated potassium channels were present. Activation of these channels was not, however, important for the efflux of anions. We measured 125I- efflux from valinomycin-depolarised cells in which anion cotransport was inhibited. Changes in 125I- efflux reflect changes in anion permeability under these conditions, and ionomycin caused a clear permeability increase that was abolished by the anion channel blocker diphenylamine-2-carboxylate. ATP and UTP increased the efflux of both isotopes, suggesting that type P2U purine receptors allow these nucleotides to regulate membrane permeability.

publication date

  • June 1, 1995

Research

keywords

  • Calcium
  • Iodine Radioisotopes
  • Rubidium Radioisotopes
  • Sweat Glands

Identity

Scopus Document Identifier

  • 0029054458

PubMed ID

  • 7788349

Additional Document Info

volume

  • 111

issue

  • 2